Content filling system and verification method of content filling system

ABSTRACT

A preform ( 31 ) is sterilized by a preform sterilizer ( 11 ). The preform ( 31 ) is blow-molded by a blow-molding device ( 13 ) to manufacture a container ( 30 ). Next, the container ( 30 ) is filled with a culture medium by a filling device ( 20 ) without sterilizing the container ( 30 ) by a container sterilizer ( 15 ), and the container ( 30 ) is plugged by a plugging device ( 21 ). Thereafter, it is verified how much microorganism survive or propagate in the culture medium in the container ( 30 ). A degree of sterilization in the container sterilizer ( 15 ) is adjusted on the basis of a verification result.

TECHNICAL FIELD

The present invention relates to a content filling system and averification method of the content filling system.

BACKGROUND ART

Conventionally, there is known an aseptic filling system in which amolding device to manufacture a container (PET bottle) by blow-molding apreform and a filling device to fill the molded container with a contentafter the container is sterilized are integrated (for example, seePatent Literature 1). Specifically, in the aseptic filling system, thecontainer molded in the molding device is conveyed to the fillingdevice. In the filling device, the container is sprayed with a hydrogenperoxide aqueous solution as a disinfectant. Thereafter, the solution isdried to sterilize the container. Then, the sterilized container isfilled with a content.

However, in the aseptic filling system of the related art, first H₂O₂ of30 μL/EA or more and 50 μL/EA or less is attached in the container inorder to achieve a high sterilization effect. Next, a large amount ofH₂O₂ attached in the container is removed by blowing, for example, hotair for 4 seconds. The reason why the time for blowing the hot air islengthened is because there is a concern about that the containercontracts in a case where a large amount of hot air is blown in a shorttime. Therefore, it is needed that a small amount of hot air is blown tothe container over a relatively long time in order to prevent thethermal contraction of the container. Therefore, there is a problem inthat the sterilization device of the aseptic filling system becomeslarge, and the costs of the aseptic filling system such as an initialcost, a running cost, and maintenance are hardly reduced. In addition,to reduce the amount of used H₂O₂ for sterilizing the container ispreferable from a viewpoint of reduction in running cost andenvironmental protection.

CITATION LIST Patent Literature Patent Literature 1: JP 2009-280222 A

The present invention has been made in view of the above problem, and anobject thereof is to provide a verification method of a content fillingsystem, and the content filling system which can suppress the cost of acontent filling system and reduce the amount of used disinfectant.

SUMMARY OF INVENTION

According to the present invention, there is provided a verificationmethod of a content filling system which includes a preform sterilizerwhich sterilizes a preform, a blow-molding device which manufactures acontainer by blow-molding the preform sterilized by the preformsterilizer, a container sterilizer which sterilizes the containermanufactured by the blow-molding device, a filling device which fillsthe container sterilized by the container sterilizer with a content, anda plugging device which plugs the container filled with the content bythe filling device. The method includes a step of sterilizing thepreform by the preform sterilizer, a step of blow-molding the preform bythe blow-molding device to manufacture the container, a step of fillingthe container with a culture medium by the filling device withoutsterilizing the container by the container sterilizer, a step ofplugging the container by the plugging device, a step of verifying howmuch microorganism survive or propagate in the culture medium in thecontainer, and a step of adjusting a degree of sterilization in thecontainer sterilizer on the basis of a verification result.

According to the verification method of the content filling system ofthe present invention, the preform sterilizer sterilizes or sanitizesthe preform by chemical spraying, chemical rinsing, steam, sterilewater, sterile air, an electronic beam, an X-ray, or an ultraviolet ray.

According to the verification method of the content filling system ofthe present invention, the container sterilizer sterilizes or sanitizesthe container by chemical spraying, chemical rinsing, steam, sterilewater, sterile air, an electronic beam, an X-ray, or an ultraviolet ray.

According to the verification method of the content filling system ofthe present invention, the step of adjusting the degree of sterilizationin the container sterilizer includes a step of adjusting a sprayingamount of a chemical agent in the container sterilizer.

According to the verification method of the content filling system ofthe present invention, the step of adjusting the degree of sterilizationin the container sterilizer includes a step of setting a sterilizationperformance of the container sterilizer such that a value ΣR₂ becomes(H₀−ΣR₁+ΣI)−FSO or more (herein, H₀ is an initial microorganism level ofthe preform, ΣR₁ is a microorganism reducing level on the preform by thepreform sterilizer, ΣI is an increase in level of microorganism on thepreform or the container between immediately after the preformsterilizer and immediately before the container sterilizer, ΣR₂ is amicroorganism reducing level on the container by the containersterilizer, and FSO is a target value of a microorganism level on thecontainer after the container passes through the container sterilizer).

According to the present invention, there is provided a verificationmethod of a content filling system which includes a container sterilizerwhich sterilizes a container, a filling device which fills the containersterilized by the container sterilizer with a content, a plugging devicewhich plugs the container filled with the content by the filling devicewith a cap, a first cap sterilizer which sterilizes the cap, an airrinse device which air-rinses the cap sterilized by the first capsterilizer, and a second cap sterilizer which sterilizes again the capair-rinsed by the air rinse device. The method includes a step ofsterilizing the container by the container sterilizer, a step of fillingthe container with a culture medium by the filling device, a step ofsterilizing the cap by the first cap sterilizer, a step of air-rinsingthe cap by the air rinse device, a step of plugging the container withthe cap by the plugging device without sterilizing the cap by the secondcap sterilizer, a step of verifying how much microorganism survive orpropagate in the culture medium in the container, and a step ofadjusting a degree of sterilization in the second cap sterilizer on thebasis of a verification result.

According to the present invention, there is provided a content fillingsystem includes a preform sterilizer which sterilizes a preform, ablow-molding device which manufactures a container by blow-molding thepreform sterilized by the preform sterilizer, a container sterilizerwhich sterilizes the container manufactured by the blow-molding device,a filling device which fills the container sterilized by the containersterilizer with a content, and a plugging device which plugs thecontainer filled with the content by the filling device. FSO is −12 ormore and −5 or less to satisfy a relation of H₀−ΣR₁+ΣI−ΣR₂≤FSO (herein,H₀ is an initial microorganism level of the preform, ΣR₁ is amicroorganism reducing level on the preform by the preform sterilizer,ΣI is the increase in level of microorganism on the preform or thecontainer between immediately after the preform sterilizer andimmediately before the container sterilizer, ΣR₂ is a microorganismreducing level on the container by the container sterilizer, and FSO isa target value of a microorganism level on the container after thecontainer passes through the container sterilizer).

According to the present invention, it is possible to suppress the costof the content filling system, and reduce the amount of useddisinfectant.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 is a schematic plan view illustrating a content filling systemwhich performs a verification method of the content filling systemaccording to a first embodiment of the present invention.

FIG. 2 is a schematic view illustrating a content filling step in thecontent filling system.

FIG. 3 is a flowchart illustrating the verification method of thecontent filling system according to the first embodiment of the presentinvention.

FIG. 4 is a schematic plan view illustrating the content filling systemwhich performs a verification method of a content filling systemaccording to a second embodiment of the present invention.

DESCRIPTION OF EMBODIMENTS First Embodiment

Hereinafter, a first embodiment of the present invention will bedescribed with reference to FIGS. 1 to 3. FIGS. 1 to 3 illustrate thefirst embodiment of the present invention.

(Content Filling System)

First, a content filling system (sterile filling system, aseptic fillingsystem) according to the present embodiment will be described withreference to FIG. 1.

A content filling system 10 illustrated in FIG. 1 is a system whichmanufactures a bottle (container) 30 by molding a preform 31 which ismanufactured by injecting and molding a synthetic resin material in abiaxial orientation blow, and fills the bottle 30 with a content such asa beverage. Materials of the preform 31 and the bottle 30 are preferablya thermoplastic resin such as polyethylene (PE), polypropylene (PP),polyethylene-terephthalate (PET), or polyethylene naphthalate (PEN).

The content filling system 10 includes a preform sterilizer 11, apreform heating device 12, a blow-molding device 13, a containerinspection device 14, a container sterilizer 15, an air rinse device 16,a container rinse device 17, a filling device 20, and a plugging device21. The preform sterilizer 11, the preform heating device 12, theblow-molding device 13, the container inspection device 14, thecontainer sterilizer 15, the air rinse device 16, the container rinsedevice 17, the filling device 20, and the plugging device 21 arearranged in this order from the upstream side toward the downstreamside. In addition, the plugging device 21 is connected to a capsterilizer 25 which sterilizes a cap 33 and at the same time conveys thecap 33 to the plugging device 21.

In the preform sterilizer 11, a chemical agent such as a hydrogenperoxide aqueous solution is sprayed from a chemical spraying nozzle 41(see FIG. 2(a)) which is disposed in the preform sterilizer 11, andsterilizes the preform 31 (preparation sterilization, a first stagesterilization). Specifically, mist or gas of the hydrogen peroxideaqueous solution is sprayed from the chemical spraying nozzle 41 to thepreform 31. With this configuration, a condensation film of hydrogenperoxide in term of 35 mass % is attached and formed in the surface ofthe preform 31 in a range of 0.0035 μL/cm² or more and 0.35 μL/cm² orless. Since the deposition amount of hydrogen peroxide becomes 0.0035μL/cm² or more, a sufficient sterilization effect can be achieved. Onthe other hand, since the deposition amount of hydrogen peroxide becomes0.35 μL/cm² or less, it is possible to prevent molding defects ofwhitening, spots, wrinkles, and deformation from the bottle in the caseof a blow molding. The condensation film of the deposition amount ofhydrogen peroxide in terms of 35 mass % with respect to the preform 31is more preferably 0.007 μL/cm² or more and 0.2 μL/cm² or less. Asillustrated in FIG. 2(a), the chemical spraying nozzle 41 may beprovided not only for the inner surface of the preform 31 but also forthe outer surface of the preform 31. In addition, a guide member 41 amay be provided at the end of the chemical spraying nozzle 41 to guidethe gas or mist of the chemical agent sprayed to the inner surface ofthe preform 31 to the screw hole of the outer side of the preform 31 soas to be sterilized.

Further, as a chlorine agent, peracetic acid, nitric acid, chlorineagent, sodium hydroxide, potassium hydroxide, ethyl alcohol, alcoholssuch as isopropyl alcohol, chlorine dioxide, ozonated water, acidicwater, and surface active agent may be used as a single body besideshydrogen peroxide, or two or more types thereof may be used by beingcombined at an arbitrary ratio.

In the preform sterilizer 11, hot air is also blown from a drying nozzle42 (see FIG. 2(b)) to dry the preform 31 after the gas or mist of thehydrogen peroxide aqueous solution is blown. With this configuration,the preform 31 is dried, and hydrogen peroxide is partially removed. Theamount of hydrogen peroxide in terms of 35 mass % attached to thepreform after drying is suitably in a range of 0.0003 μL/cm² or more and0.35 μL/cm² or less. The deposition amount of hydrogen peroxide becomes0.0003 μL/cm² or more, so that a sufficient sterilization effect can beachieved. On the other hand, since the deposition amount of hydrogenperoxide becomes 0.35 μL/cm² or less, it is possible to prevent moldingdefects such as whitening, spots, wrinkles, and deformation from thebottle in the case of a blow molding. The condensation film of thedeposition amount of hydrogen peroxide in terms of 35 mass % withrespect to the preform 31 is more preferably 0.0004 μL/cm² or more and0.2 μL/cm² or less. Further, the drying nozzle 42 may be not necessarilyprovided.

Further, the preform sterilizer 11 may be configured to sterilize thepreform 31 with a chemical rinse. In this case, the preform sterilizer11 may rinse the inside of the preform 31 using, for example, a chemicalagent, and air-rinse the preform 31 to remove the chemical agent. Theair-rinsing may be performed using sterile air. The air may beblower-air or compressed air. In addition, after the inside of thepreform 31 is rinsed by the chemical agent, the preform 31 may be rinsedwith water to remove the chemical agent such as peracetic acid.Alternatively, the preform sterilizer 11 may be configured to rinse theinside of the preform 31 with hot water (sterile water).

As a chemical agent, water containing hydrogen peroxide by 1 wt. % ormore and 35 wt. % or less, or peracetic acid by 100 ppm or more and 5000ppm or less, or preferably by 500 ppm or more and 3000 ppm or less. Inaddition, as a chemical agent, two or more types of the above chemicalagents (hydrogen peroxide, peracetic acid, nitric acid, chlorine agent,sodium hydroxide, potassium hydroxide, ethyl alcohol, alcohols such asisopropyl alcohol, chlorine dioxide, ozonated water, acidic water,surface active agent) may be used by combining at an arbitrary ratio.Further, in a case where a solution (hydrogen peroxide concentration:0.1 wt. % or more and 35 wt. % or less, or preferably 1 wt. % or moreand 25 wt. % or less) obtained by diluting hydrogen peroxide water withalcohols such as ethanol is used as a chemical agent, volatility isincreased. Therefore, the rinsing air or the rinsing water to remove thechemical agent may be reduced. In addition, any chemical agent may beused as long as the chemical agent inactivates microorganism, and is notlimited to the above examples.

In addition, the preform sterilizer 11 may sterilize the preform 31 withsteam such as water vapor. In this case, the preform sterilizer 11 mayspray the water vapor to the inside of the preform 31 for example, andair-rinse the preform 31. Further, the air-rinsing may be not omitted.

In addition, the preform sterilizer 11 may be configured to sterilizethe preform 31 with an electronic beam, an X-ray, or an ultraviolet ray.In this case, the preform sterilizer 11 may be configured to irradiatethe inside of the preform 31 with, for example, the electronic beam (EB)or the X-ray, and to air-rinse the preform 31. Further, the air-rinsingmay be not preformed. Alternatively, the preform sterilizer 11 may beconfigured to irradiate the inside of the preform 31 with theultraviolet ray to sterilize the preform 31.

With reference to FIG. 1, the preform heating device 12 is configured toheat the preform 31 which is sterilized by the preform sterilizer 11. Inthe preform heating device 12, a heater 43 is disposed in a tunnel shapealong a conveyance path of the preform 31. The preform 31 is heated bythe heater 43 while running (see FIG. 2(c)). The preform 31 is evenlyheated at about 90° C. to 130° C. in this heating, and enters a heatedstate to be suitable to a blow molding.

At the time of heating, the preform 31 is evenly heated in acircumferential direction by the heater 43 such that a spindle (ormandrel; not illustrated) 44 (see FIG. 2(c)) is inserted to the mouthpart, hanged in an erected state (or an inverted attitude), and rotatedtogether with the spindle (or mandrel) 44.

In addition, the surface of the preform 31 is pre-sterilized by theheating step. In other words, the preform 31 is dried while being heatedin a state where the condensation film of the chemical agent (forexample, hydrogen peroxide) is attached. Therefore, the concentration ofthe hydrogen peroxide aqueous solution attached to the sterilizingsurface is increased, so that a high sterilization effect is achieved,and heat-resistant mold or spore forming microorganism are easilysterilized. In addition, even in a case where the preform 31 is treatedwith the chemical agent by the preform sterilizer 11, and air-rinsed, asmall amount of chemical agent is absorbed in the resin of the preform31. Therefore, the remaining chemical agent is heated together withmicroorganism in the heating step, and a high sterilization effect isrealized. With this configuration, eumycetes such as generalmicroorganism, spore-forming microorganism, and mold/yeast attached tothe surface of the preform 31 are preferably sterilized.

The preform 31 heated by the preform heating device 12 so as to enter aheated state suitably to the blow molding and pre-sterilized is conveyedto the blow-molding device 13. In the blow-molding device 13, thepreform 31 is molded in a biaxial orientation blow, and molded to thebottle 30.

In the blow-molding device 13, the preform 31 is inserted into a die 45(see FIG. 2(d)) which is a molding die for the blow molding. The die 45enters a mold-clamping state while continuously running at the samespeed as the running speed of the preform 31, and enters a mold-openstate after the blow molding is performed on the preform 31 in the die45.

The preform 31 is almost evenly heated such that the entire temperatureis increased to a temperature range in the heating step to be suitableto the molding. After the heating step ends, the preform is conveyed toa blow station of the blow-molding device 13, and mounted in the die 45.In addition, a stretching rod 46 (see FIG. 2(d)) passes through theupper portion of the die 45 and a blow nozzle 44 a in the mouth part ofthe preform 31 so as to be inserted into the preform 31. During whichthe die 45 runs, for example, a primary blowing air and a secondaryblowing air are sequentially blown into the preform 31 through the blownozzle 44 a, and the preform 31 is expanded up to the bottle 30 of afinal molded product in a cavity of the die 45. In this way, if thebottle 30 is molded in the die 45, the die 45 opens while running, and afinished product of the bottle 30 is taken out of the die 45.

With reference to FIG. 1, a plurality of conveying mechanisms (conveyingwheels) 18 are disposed in the content filling system 10 to convey thepreform 31 and/or the bottle 30. Further, the configurations of thepreform heating device 12 and the blow-molding device 13 are notparticularly limited, and a generally available device may be used. Forexample, the blow-molding device 13 is not limited to the rotarymechanism as illustrated in FIG. 1, and may be a linear mechanism.

The container inspection device 14 is positioned on the downstream sideof the blow-molding device 13, and inspects the bottle 30 which ismanufactured by the blow-molding device 13. The container inspectiondevice 14 inspects deformation or scratches of the bottle 30. As such acontainer inspection device 14, a bottle inspection device which isconventionally used may be employed.

The container sterilizer 15 sterilizes the interior of the bottle 30 byinjecting a disinfectant into the bottle 30 (a main sterilization, asecond stage sterilization). With this configuration, the bottle 30 issterilized by a disinfectant before the content is filled, andmicroorganism) spores, nutritive cells, mold, and yeast are sterilized.As the disinfectant, the chemical agent such as a hydrogen peroxideaqueous solution is used. In the container sterilizer 15, mist or gas ofthe hydrogen peroxide aqueous solution is generated, and the mist or gasis sprayed on inner and outer surfaces of the bottle 30. Since theinside of the bottle 30 is thus sterilized by the mist or gas of thehydrogen peroxide aqueous solution, the inner and outer surfaces of thebottle 30 is sterilized uniformly.

In the container sterilizer 15, the chemical agent such as the hydrogenperoxide aqueous solution is sprayed from a chemical spraying nozzle 47(see FIG. 2(e)) disposed in the inner and outer surfaces of thecontainer sterilizer 15, and the bottle 30 is sterilized. Specifically,the mist or gas of the hydrogen peroxide aqueous solution is blown fromthe chemical spraying nozzle 47 to the bottle 30.

At this time, the heating by the preform 31 and the heat caused from thedie is left in the bottle 30. With this heat, the sterilization effectis increased by the mist and gas of the hydrogen peroxide aqueoussolution. As described above, the preparation sterilization is performedon the preform 31, and almost the microorganisms attached to the preform31 are sterilized through the preparation sterilization. Therefore, withthe blowing of the mist or gas of the hydrogen peroxide aqueous solutionto the bottle 30, microorganism survived at the stage of the preform 31and a small amount of microorganism mixed into the blow molding step andthe conveying step are sterilized in the main sterilization.

Further, the container sterilizer 15 may be configured to sterilize thebottle 30 with a chemical rinse. In this case, the container sterilizer15 may rinse the inside of the bottle 30 with the chemical agent such asperacetic acid, and rinse the bottle 30 with water (sterile water) toremove the chemical agent such as peracetic acid. Alternatively, thecontainer sterilizer 15 may be configured to rinse the inside of thebottle 30 with hot water of 60° C. or more and 90° C. or less.

In addition, the container sterilizer 15 may be configured to sterilizethe bottle 30 with the electronic beam, the X-ray, or the ultravioletray. In this case, the preform sterilizer 11 may be configured toirradiate the inside of the bottle 30 with, for example, the electronicbeam (EB) or the X-ray, and to air-rinse the bottle 30. Alternatively,the container sterilizer 15 may be configured to sterilize the preform31 by rinsing the bottle 30 with the sterile air or the sterile waterwhile irradiating the inside of the preform 31 with the ultraviolet ray.

The air rinse device 16 is configured to perform cleaning by blowing thesterile air of 50° C. or more and 180° C. or less (preferably, 70° C. ormore and 140° C. or less) to the bottle 30 sterilized by hydrogenperoxide (disinfectant). With this configuration, the hydrogen peroxideattached to the bottle 30 is removed, and a foreign matter is removed.Further, the air rinse device 16 may be not necessarily provided. Inaddition, the air-rinsing may be performed in a state where the bottle30 is erected, but the invention is not limited thereto. The air-rinsingmay be performed in a state where the bottle 30 is inversed. With thisconfiguration, the removal of the foreign matter can be performedsimultaneously.

The container rinse device 17 sterilizes the bottle 30, sterilized by ahydrogen peroxide aqueous solution as a disinfectant, with hot water.Specifically, for example, hot water having a temperature of 65° C. ormore and 80° C. or less is supplied into the bottle 30. Further, thecontainer rinse device 17 may be not necessarily provided.

In addition, when sterilizing the bottle 30, the invention is notlimited to one sterilization method. Two types of sterilization methodsmay be combined.

The filling device 20 fills the previously sterilized content from themouth of the bottle 30 into the bottle 30. This filling device 20 fillsthe content in the empty bottle 30 from a filling nozzle 48 (see FIG.2(f)). In this case, in the filling device 20, the content is filled tothe inside of the bottles 30 while a plurality of the bottles 30 arerotated (revolved). This content may be filled into the bottle 30 atroom temperature. The content is previously sterilized by heating or thelike, cooled to room temperature of 3° C. or more and 40° C. or less,and then filled into the bottle 30.

The plugging device 21 is configured to plug the bottle 30 by mountingthe cap 33 to the mouth part of the bottle 30. In the plugging device21, the mouth part of the bottle 30 is plugged by the cap 33, and sealedsuch that the outer air and microorganisms do not permeate into thebottle 30 (see FIG. 2(g)). In the plugging device 21, the cap is mountedin the mouth part while a plurality of bottles 30 filled with thecontent rotates (revolves). Thus, the cap 33 is attached to the mouth ofthe bottle 30, so that a product bottle 35 is obtained.

A product bottle conveyor 22 is configured to continuously convey theproduct bottle 35 with the cap 33 mounted by the plugging device 21toward the outside of the content filling system 10.

In addition, the content filling system 10 includes a sterile chamber70. The container sterilizer 15, the air rinse device 16, the containerrinse device 17, the filling device 20, and the plugging device 21 arestored in the inside of the sterile chamber 70. This content fillingsystem 10 may be, for example, a sterile filling system. In this case,the interior of the sterile chamber 70 is kept in a sterile state.

(Content Filling Method)

Next, a content filling method using the above-described content fillingsystem 10 (FIG. 1) will be described. In the following description, afilling method at a normal time, that is, a content filling method inwhich a content such as a beverage is actually filled inside the bottle30 to produce the product bottle 35 will be described.

First, the preform 31 is brought into the preform sterilizer 11. In thepreform sterilizer 11, a chemical agent such as a hydrogen peroxideaqueous solution is sprayed from a chemical spraying nozzle 41 (see FIG.2(a)) which is disposed in the preform sterilizer 11, and sterilizes thepreform 31 (preform sterilization step). Subsequently, in the preform31, hot air is blown from the drying nozzle 42 (see FIG. 2(b)) so thatthe preform 31 is dried, and the sterilization starts while hydrogenperoxide is partially removed.

Next, the preform 31 is sent to the preform heating device 12. In thepreform heating device 12, the preform 31 is heated by the heater 43(see FIG. 2(c)) while the preform 31 runs (preform heating step). Withthis configuration, the preform 31 enters a heated state suitable to theblow molding, and the surface thereof is pre-sterilized.

Subsequently, the preform 31 is conveyed to the blow-molding device 13.In the die 45 of the blow-molding device 13 (see FIG. 2(d)), the preform31 is biaxially expanded and blow-molded, and is molded to the bottle 30(bottle molding step).

The bottle 30 manufactured by the blow-molding device 13 is conveyed tothe container inspection device 14. Next, the blow-molding device 13inspects deformation and scratches of the bottle 30 (containerinspection step). In a case where there is deformation or scratches inthe bottle 30 detected by the container inspection device 14, the bottle30 discharges the bottle from the container inspection device 14 to theoutside of the content filling system 10.

Next, the bottle 30 passed through the container inspection device 14 issent to the container sterilizer 15. In the container sterilizer 15, thebottle 30 is sterilized using the hydrogen peroxide aqueous solution asa disinfectant (container sterilization step). At this time, thehydrogen peroxide aqueous solution is gas or mist vaporized once at atemperature not less than the boiling point, and is supplied toward thebottle 30. The mist of the hydrogen peroxide aqueous solution isattached to the entire outer surface of the bottle 30, and sterilizesmicroorganism attached to the bottle 30. The deposition amount of thegas and the mist of hydrogen peroxide supplied into the bottle 30 ispreferably a range of 0.01 μL/cm² or more and 0.1 μL/cm² or less interms of 35 mass %. The deposition amount of hydrogen peroxide becomes0.01 μL/cm² or more, so that the sterilization effect can be evenlyachieved over the entire bottle. On the other hand, if the depositionamount of hydrogen peroxide becomes 0.1 μL/cm² or less, a time taken forthe air rinse to remove the remaining hydrogen peroxide becomes not toolong, and thus economical. The condensation film of the depositionamount of hydrogen peroxide in terms of 35 mass % with respect to theinner surface of the bottle 30 more preferably falls within 0.03 μL/cm²or more and 0.07 μL/cm² or less.

Subsequently, the bottle 30 is conveyed from the container sterilizer 15to the air rinse device 16. In the air rinse device 16, the bottle 30 isblown with the sterile air of 50° C. or more and 180° C. or less(preferably, 70° C. or more and 140° C. or less), so that the bottle 30is cleansed. With this configuration, hydrogen peroxide attached to thebottle 30 is removed, and the foreign matter in the bottle 30 isremoved.

Next, the bottle 30 is conveyed from the air rinse device 16 to thecontainer rinse device 17. In the container rinse device 17, the bottle30 sterilized with hydrogen peroxide (disinfectant) is subjected tosterilization with water or hot water. Specifically, water of atemperature of 10° C. or more and 85° C. or less or hot water issupplied into the bottle 30 at a flow rate of 5 L/min or more and 15L/min or less.

At this time, it is preferable that the bottle 30 takes an invertedattitude, and the water or hot water is supplied into the bottle 30through the downwardly opened mouth, and the hot water flows out of thebottle 30 from the mouth. An excess hydrogen peroxide aqueous solutionremaining in the bottle 30 and the foreign matter are washed off withthe water or the hot water, and discharged from the bottle 30 outward.In some cases, the rinsing may be performed on the outer surface of thebottle 30 with the water or the hot water similarly to the innersurface. Further, such a rinsing step of the container rinse device 17may be not necessarily provided.

Subsequently, the bottle 30 is conveyed from the container rinse device17 to the filling device 20. In the filling device 20, the bottle 30 isfilled with the content by the filling nozzle 48 (see FIG. 2(f)) whilethe bottle 30 rotates (revolves) (filling step). Further, the content ismixed in advance before filled into the bottle 30 by the filling device20, and a heating sterilization treatment is performed. A heatingtemperature is about 60° C. or more and 150° C. or less. As a result,microorganisms which may be grown in the product bottle 35 in thecontent before the filling thereof can be completely sterilized. Thecontent after the heating sterilization treatment is cooled to the roomtemperature of about 3° C. or more and 40° C. or less. In the fillingdevice 20, the sterilized bottle 30 is filled at the room temperaturewith the content sterilized and cooled to the room temperature. Thetemperature of the content during filling is, for example, about 3° C.or more and 40° C. or less.

Subsequently, the bottle 30 filled with the content is conveyed from thefilling device 20 to the plugging device 21. Next, in the pluggingdevice 21, the sterilized cap 33 which is sterilized by the capsterilizer 25 is mounted in the mouth part of the bottle 30, so that theproduct bottle 35 is obtained (see FIG. 2(g)) (cap mounting step).

Thereafter, the product bottle 35 is conveyed from the plugging device21 to the product bottle conveyor 22, and conveyed toward the outside ofthe content filling system 10.

Further, the steps from the container sterilization step to the capmounting step are performed in a sterile atmosphere surrounded by thesterile chamber 70, that is, in a sterile environment. After thesterilization treatment, sterile air of positive pressure is suppliedinto the sterile chamber 70 so that the sterile air is always blowntoward the outside of the sterile chamber 70.

In addition, the production (conveying) speed of the bottle 30 in thecontent filling system 10 is preferably 100 bpm or more and 1500 bpm orless. Here, the conveying speed of the bottle 30 per minute is referredto as bottle per minute (bpm).

(Method for Verifying Content Filling System)

Next, the description will be given about a verification method of thecontent filling system according to this embodiment to verify amicroorganism contamination level of the content filling system 10 (FIG.1).

The verification method according to this embodiment is configured tocheck a microorganism contamination level in the content filling system10, especially, from the preform sterilizer 11 to the containersterilizer 15. This verification method may be performed, for example,at an early stage immediately after the content filling system 10 iscompleted, that is, before the product bottle 35 starts to be producedwhen the bottle 30 is filled by actually using the content fillingsystem 10. Alternatively, the verification method may be performed in acase where there is a concern of an influence on the microorganismcontamination level such as a case where there occurs a change in a stepor a device in the content filling system 10, or in a case where thecontent filling system 10 has not been used for a while. Alternatively,the verification method may be regularly performed at every fillingcycle regardless of the influence of the microorganism contaminationlevel.

In addition, a maintenance work of the content filling system 10 may beperformed before the verification method according to this embodiment isperformed on an assumption of a case where the microorganismcontamination level from the preform sterilizer 11 to the containersterilizer 15 is highest. For example, the die 45, the blow nozzle, andthe stretching rod 46 of the blow-molding device 13 may be replaced, ora lamp of the heater 43 of the preform heating device 12 may bereplaced. In addition, the works may be performed on an assumption thata maximum number of operators participate in molding and filling.

After the maintenance work is performed, the microorganism contaminationlevel of the content filling system 10 is evaluated, and theverification method according to this embodiment using the bottle 30filled with a culture medium is performed in order to adjust the degreeof sterilization in the container sterilizer 15. Specifically, a numberof preforms 31 sterilized by the preform sterilizer 11 is blow-molded bythe blow-molding device 13 to manufacture a number of bottles 30. Then,each bottle 30 is filled with a predetermined culture medium instead ofthe content actually filled therein. Thereafter, it is checked how muchthe culture medium filled in each bottle 30 is decayed after apredetermined time elapses.

Hereinafter, the verification method of the content filling system 10according to this embodiment will be described with reference to FIGS. 1and 3. FIG. 3 is a flowchart illustrating the verification methodaccording to this embodiment.

First, a number of preforms 31 are brought into the preform sterilizer11 from the outside. Each preform is sterilized in the preformsterilizer 11 (preform sterilization step, step S1 of FIG. 3). Thenumber of preforms 31 used in the verification method of the contentfilling system 10 is set in advance, and may be 1,000 or more and300,000 or less for example (preferably, 3,000 or more and 30,000 orless).

Next, each preform 31 is heated by the preform heating device 12(preform heating step, step S2 of FIG. 3). Then, in the blow-moldingdevice 13, the preform is biaxially expanded and blow-molded so as toform the bottle 30 (blow molding step, step S3 of FIG. 3).

The bottle 30 manufactured by the blow-molding device 13 is inspected inthe container inspection device 14 (container inspection step, step S4of FIG. 3). The bottle 30 passed through the container inspection device14 is sent to the container sterilizer 15.

Further, each step from the preform sterilization step to the containerinspection step is similar to each step from the preform sterilizationstep to the container inspection step in the normal content fillingmethod described above.

In this case, the container sterilizer 15 is stopped, and the bottle 30is sent to the filling device 20 without the sterilization of thecontainer sterilizer 15. Further, during that period, the bottle 30 maybe blown with the sterile air by the air rinse device 16. Alternatively,the air rinse device 16 is stopped, and the bottle 30 may be sent to thefilling device 20 without blowing the sterile air.

In addition, the sterile air may be blown under an air volume conditionof the air rinsing in the air rinse device 16 having a foreign matter(microorganism) removing performance as a lower limit (or less than thelower limit) of a production condition.

In addition, in a case where the container rinse device 17 is installed,the bottle 30 is sent to the filling device 20 without the sterilizationwith water or hot water in the container rinse device 17. Further,during that period, the bottle 30 may be blown with the sterile air bythe air rinse device 16. Alternatively, the container rinse device 17 isstopped, and the bottle 30 may be sent to the filling device 20 withoutblowing water or hot water. In addition, the rinsing may be performed ona flow rate/temperature condition of rinsing with water or hot water inthe container rinse device 17 having the foreign matter (microorganism)removing performance as a lower limit (or less than the lower limit) ofa production condition.

Next, in the filling device 20, a predetermined amount of culture mediumis filled from the mouth part of the bottle 30 into the bottle 30(culture medium filling step, step S5 in FIG. 3). The culture medium isprepared in advance before filled into the bottle 30 by the fillingdevice 20, and heating sterilization treatment is performed. The pH ofthe culture medium is adjusted in accordance with the characteristic ofthe content. For example, the culture medium may be an acid culturemedium of 4.0 pH or more and 4.6 pH or less, or may be a neutral culturemedium of 6.5 pH or more and 7.5 pH or less.

Such a culture medium is generally formed by dissolving in water 0.2 to3 wt. % of glucose which is an organic carbon source, monosaccharidessuch as dextrose, disaccharides, polysaccharides, sodium carbonate,which is an inorganic carbon source, or sodium bicarbonate as a carbonsource, 0.5 to 3 wt. % of casein peptone, chicken peptone, cardiacmuscle peptone, gelatin peptone, soybean peptone, polypeptone, yeastextract, meat extract, ammonium sulfate, magnesium sulfate, nitrate orthe like as a nitrogen source (including coenzyme), and 0.05 to 1 wt. %of sodium chloride, monopotassium phosphate, potassiummonohydrogenphosphate, potassium dihydrogenphosphate or the like as atrace mineral or a buffering agent. The pH of the culture medium isadjusted by dissolving hydrochloric acid, tartaric acid, citric acid,sodium hydroxide, potassium hydroxide or the like in the culture medium.

Subsequently, the bottle 30 filled with the culture medium is sent tothe plugging device 21. In the plugging device 21, the sterilized cap 33which is sterilized by the cap sterilizer 25 is mounted in the mouthpart of the bottle 30 (cap mounting step, step S6 of FIG. 3). The capmounting step is executed similarly to the cap mounting step in theordinary content filling method described above.

In this way, the culture medium is filled into the bottle 30, and themouth part is tightly plugged with the cap 33, whereby a verificationbottle 36 is obtained.

Then, the verification bottle 36 filled with the culture medium isconveyed from the product bottle conveyor 22 to the outside. Thereafter,a plurality of verification bottles 36 are conveyed to a constanttemperature storage (not illustrated) maintained at a predeterminedtemperature of 25° C. or more and 40° C. or less, and left and culturedin the constant temperature storage (culture step, step S7 of FIG. 3).Further, in a case where the product bottle 35 is warmed and sold by ahot bender, it is necessary to check sterility against thermophilicmicroorganism, and the verification bottle 36 may be cultured at atemperature of 40° C. or more and 65° C. or less.

After a lapse of a predetermined period (for example, three days ormore, preferably seven days or more), all the verification bottles 36are taken out from the constant temperature storage, and how muchmicroorganism survive or propagate in the culture medium in theverification bottle 36 is verified (verifying step, step S8 in FIG. 3).It is assumed that the result obtained in the verifying step correspondsto the microorganism contamination level from the preform sterilizer 11to the container sterilizer 15. Further, the verifying step is notlimited to the verification using the culture medium, and may beperformed in replacement of an actual product or an easily decayingproduct (for example, a milk-containing beverage).

Thereafter, the sterilization degrees in the container sterilizer 15,the air rinse device 16, and the container rinse device 17 are adjustedon the basis of the result in the verifying step (adjusting step, stepS9 of FIG. 3). The adjustment of the sterilization degree in theadjusting step may be performed, for example, by appropriately settingthe performances of the container sterilizer 15, the air rinse device16, and the container rinse device 17 (specifically, by adjusting aspraying amount (deposition amount) of the chemical agent in thecontainer sterilizer 15, an air-blow time in the air rinse device 16, anair volume, an air temperature, the temperature of hot water in thecontainer rinse device 17, the volume of hot water, and an amount ofused hot water such as a rinsing time). Alternatively, the installationarea of the container sterilizer 15, the air rinse device 16, and thecontainer rinse device 17 may be adjusted to shorten the time when thebottle passes through these devices.

For example, the spraying amount of the chemical agent and the amount ofused air, water, or hot water may be restricted while keepingsterilization performances required in the container sterilizer 15, theair rinse device 16, and the container rinse device 17 by adjusting thespraying amount of the chemical agent in the container sterilizer 15,the amount of used air in the air rinse device 16, and the amount ofused water or hot water in the container rinse device 17. With thisconfiguration, the costs required for sterilization can be reduced, andan environmental load can be alleviated. In addition, since theinstallation area of the container sterilizer 15, the air rinse device16, and the container rinse device 17 is saved, the size of the contentfilling system 10 can be made compact.

Herein, the adjusting step will be described again. In general, thereare microorganism already in the preform 31 before brought into thepreform sterilizer 11. An initial microorganism level of the preform 31is set to H₀ (=log N₀). In this case, the initial microorganism level H₀of the preform 31 is affected by the sterilization effect (which isreduced by a microorganism reducing level ΣR₁ (=log(N₀/N_(R1))>0), andbecomes an intermediate contamination between immediately after thepreform sterilizer 11 and immediately before the container sterilizer 15(the increase in level of microorganism: ΣI (=log(N_(I))≥0)) of thepreform sterilizer 11. Therefore, the microorganism attached to thebottle 30 are increased at a certain ratio. At this time, themicroorganism attached to the bottle 30 are reduced again by thesterilization effect (the microorganism reducing level: ΣR₂(=log(N_(I)/N_(R2))>0)) of the container sterilizer 15, the air rinsedevice 16, and the container rinse device 17. Further, in a step afterthe filling device 20, it is assumed that the contamination can beignored because a sterilization filling facility is used. Therefore, ifa microorganism level per one bottle after passing through the containersterilizer 15, the air rinse device 16, or the container rinse device 17falls to equal to or less than a target value (FSO (Food SafetyObjective/ISO13409-1996) (=log N)), it can be considered to have noprogram in the sterility of the content filling system 10. The followingexpression represents the above description. Further, “N₀” representsthe initial number of microorganism per one preform, “N_(R1)” representsthe number of microorganism per one preform after being sterilized bythe preform sterilizer 11, “N_(I)” represents the number ofmicroorganism per one bottle after being intermediately contaminatedbetween immediately after the preform sterilizer 11 and immediatelybefore the container sterilizer 15, “N_(R2)” represents the number ofmicroorganism per one bottle after being sterilized by the containersterilizer 15, the air rinse device 16, and the container rinse device17, and “N” represents a target value of the number of microorganism perone bottle after being sterilized by the container sterilizer 15, theair rinse device 16, and the container rinse device 17.

H ₀ −ΣR ₁ +ΣI−ΣR ₂ ≤FSO  (Expression 1)

In the verification method, since the container sterilizer 15, the airrinse device 16, and the container rinse device 17 are stopped, ΣR₂ of(Expression 1) becomes 0. Therefore, the result obtained by theverifying step corresponds to the value H₀−ΣR₁+ΣI in (Expression 1). Thevalue is larger than a normal FSO. Therefore, the sterility of thecontent filling system 10 can be made equal to or less than the targetvalue (FSO) by setting the sterilization performances of the containersterilizer 15, the air rinse device 16, and the container rinse device17 such that the value ΣR₂ becomes equal to or more than(H₀−ΣR₁+ΣI)−FSO.

According to this embodiment as described above, how much microorganismsurvive or propagate in the culture medium in the bottle 30 is verified.The sterilization degrees of the container sterilizer 15, the air rinsedevice 16, and the container rinse device 17 are adjusted on the basisof the verification result. With this configuration, the spraying amountof the chemical agent in the container sterilizer 15, the air-rinsingcondition of the air rinse device 16 (temperature, volume, time), or theinstallation area of the container sterilizer 15, the air rinse device16, and the container rinse device 17 can be restricted whilemaintaining the sterilization degree required for the content fillingsystem 10. As a result, a running cost of the content filling system 10can be reduced, and an environmental load can be alleviated. Inaddition, the content filling system 10 can be configured compact.

Examples

Next, specific examples of the present embodiment will be described.

First, the plurality of preforms 31 were sequentially sterilized usingthe preform sterilizer 11 of the content filling system 10. The eachsterilized preform 31 was blow-molded using the blow-molding device 13to manufacture the bottle 30. Each bottle 30 was sent to the containersterilizer 15, the air rinse device 16, and the container rinse device17 sequentially, and sent to the filling device 20 without beingsterilized by the container sterilizer 15, the air rinse device 16, andthe container rinse device 17. Next, the bottle 30 was filled with theculture medium at a room temperature using the filling device 20,plugged with the cap 33, and cultured for one week at 30° C. Further,the number of the cultured bottles 30 was 75,432 in total. Afterculturing, it was confirmed that there were two bottles 30 of which theculture medium was decayed as a result of inspecting all the bottles 30.Therefore, the number of microorganism per obtained one bottle wasestimated at 2/75,432=about 10⁻⁴, and the value H₀−ΣR₁+ΣI was estimatedat log(10⁻⁴)=−4.

On the other hand, the target value (FSO) of the microorganism level inthe content filling system 10 is, for example, −7. Therefore, it isconsidered that a sterilization level of the content filling system 10can be reached to the target value (FSO=−7) by setting the sterilizationperformance of the container sterilizer 15 to −4−(−7)=3 LRV (LogReduction Level), that is, ΣR₂=3. Thus, the spraying amount of thechemical agent (hydrogen peroxide solution) in the container sterilizer15 was adjusted to get a spraying amount of 15.2 kg/h in order to setthe sterilization performance of the container sterilizer 15 to 3 LRV.It was the spraying amount was reduced by about 40% more than that ofthe hydrogen peroxide solution used in the conventional containersterilizer 15. Therefore, it was confirmed that the amount of usedhydrogen peroxide solution in the container sterilizer 15 can bereduced. In general, a target value of the sterility level in FSO isdesirably set within a range of −12 or more and −5 or less, anddesirably within a range of −10 or more and −6 or less depending onmicroorganism to be targeted. If FSO is set higher than −5, safetyissues occur. On the other hand, if the sterility rises until FSObecomes a level lower than −12, energy and costs increase which is noteconomical. In this embodiment, there is also provided the contentfilling system 10 of which the sterility level (H₀−ΣR₁+ΣI−ΣR₂) reachesthe target value (FSO is −12 or more and −5 or less).

Second Embodiment

Next, a second embodiment of the present invention will be describedwith reference to FIG. 4. FIG. 4 is a diagram illustrating the secondembodiment of the present invention. The second embodiment illustratedin FIG. 4 is mainly configured to sterilize the cap 33 in two stages.The same portions in FIG. 4 as those in the first embodiment will beattached with the same symbol, and the detailed description will beomitted.

As illustrated in FIG. 4, a content filling system 10A according to thisembodiment includes the preform sterilizer 11, the preform heatingdevice 12, the blow-molding device 13, the container inspection device14, the container sterilizer 15, the air rinse device 16, the containerrinse device 17, the filling device 20, and the plugging device 21.Further, the configurations of the preform sterilizer 11, the preformheating device 12, the blow-molding device 13, the container inspectiondevice 14, the container sterilizer 15, the air rinse device 16, thecontainer rinse device 17, the filling device 20, and the pluggingdevice 21 are almost the same as those illustrated in the firstembodiment, and the detailed description will be omitted.

The plugging device 21 is connected to a cap sterilization unit 60 whichsterilizes the cap 33 and conveys the sterilized cap 33 to the pluggingdevice 21. The cap sterilization unit 60 includes a first cap sterilizer61 which sterilizes the cap 33, an air rinse device 62 which air-rinsesthe sterilized cap 33 by the first cap sterilizer 61, a second capsterilizer 63 which sterilizes again the cap 33 air-rinsed by the airrinse device 62.

The cap 33 is a well-known cap of which the flat surface is almost acircle shape having an opening on the inner surface side. Further, asthe cap 33, high density polyethylene (HDPE), polypropylene (PP), andthermoplastic resin such as biodegradable plastic may be used. Inaddition, as the cap 33, a composite cap or a sport cap may be usedbesides a normal bottle cap.

The first cap sterilizer 61 is configured to spray chemical gas or mistsuch as the hydrogen peroxide aqueous solution to the cap 33 which isconveyed. The deposition amount of hydrogen peroxide required for thefirst cap sterilizer 61 to sterilize the cap 33 is 0.6 μL/cm² or moreand 4.7 μL/cm² or less in terms of 35 wt. % (preferably, 1.2 μL/cm² ormore and 2.4 μL/cm² or less). The first cap sterilizer 61 is installedin a hopper or a sorter 64 which arranges and conveys the randomlyinserted caps 33.

The second cap sterilizer 63 is installed on a side near a fillingmachine, and is configured to spray the chemical gas or mist such as thehydrogen peroxide aqueous solution to the cap 33. The cap 33 is conveyedfrom the first cap sterilizer 61 up to the second cap sterilizer 63 on aside near the plugging device 21, and is sterilized by the chemicalagent such as the hydrogen peroxide aqueous solution.

The air rinse device 62 is installed on a downstream side of the secondcap sterilizer 63, and is configured to convey the cap 33 to which thechemical agent is sprayed and to air-rinse the conveyed cap 33. The cap33 is sequentially conveyed in the air rinse device 62 and, during that,the inner surface and the outer surface of the cap 33 is blown with thesterile hot air. The temperature of the sterile hot air blowing in theair rinse device 62 is, for example, 80° C. or more and 140° C. or less,or preferably 90° C. or more and 120° C. or less. The wind volume of thesterile hot air is, for example, 5 m³/min or more and 20 m³/min or less.In addition, a blow time of the sterile hot air is 0.5 seconds or moreand 20 seconds or less, or preferably 1 second or more and 14 seconds orless. When the sterile hot air blows, the temperature of the cap 33 isincreased to 40° C. or more, or preferably 50° C. or more. With thisconfiguration, the chemical agent attached to the cap 33 is removed.Further, a minute amount of the component of the chemical agent such ashydrogen peroxide may be contained in the sterile hot air. With thisconfiguration, it is possible to securely remove the chemical agentattached to the cap 33 using the second cap sterilizer 63.

(Cap Sterilization Method)

Next, a cap sterilization method using the cap sterilization unit 60 ofthe content filling system 10A will be described. Further, the followingdescription will be given about a cap sterilization method at a normaltime, that is, a cap sterilization method when the content such as abeverage is filled in the bottle 30 to manufacture the product bottle35.

First, a number of caps 33 are brought into from the outside of the capsterilization unit 60. Next, the caps 33 are arranged by the hopper orthe sorter 64, and conveyed in the cap sterilization unit 60.

During that period, the cap 33 is sprayed with the chemical agent suchas the hydrogen peroxide aqueous solution in the first cap sterilizer 61installed in the hopper or the sorter 64, and the inner and outersurfaces thereof are sterilized.

Next, the cap 33 is delivered from the first cap sterilizer 61 to thesecond cap sterilizer 63 on a side near the plugging device 21. Next, inthe second cap sterilizer 63, the cap 33 is sprayed with chemical gas asor mist of the chemical agent such as the hydrogen peroxide aqueoussolution while being rotatably conveyed, and the inner and outersurfaces thereof are sterilized.

Subsequently, the cap 33 sprayed with the chemical agent is delivered tothe air rinse device 62. In the air rinse device 62, the cap 33 isconveyed and, during that, the inner and outer surfaces of the cap 33with the sterile hot air during conveyed. With this configuration, thechemical agent attached to the cap 33 is air-rinsed.

In this way, in the plugging device 21, the cap 33 sterilized by the capsterilization unit 60 is mounted in the mouth part of the bottle 30which is conveyed from the filling device 20. With this configuration,the product bottle 35 which includes the bottle 30 and the cap 33 isobtained.

Thereafter, the product bottle 35 is conveyed from the plugging device21 to the product bottle conveyor 22, and conveyed toward the outside ofthe content filling system 10.

(Method for Verifying Content Filling System)

Next, a verification method of the content filling system 10A will bedescribed.

First, a number of caps 33 are sterilized in the first cap sterilizer 61(first sterilization step of the cap). The number of caps 33 used in theverification method of the content filling system 10A is set in advance.For example, the number of caps may be 1,000 or more and 300,000 or less(preferably, 3,000 or more and 30,000 or less).

Next, the cap 33 is delivered from the first cap sterilizer 61 to thesecond cap sterilizer 63. In this case, the second cap sterilizer 63 isstopped, and the bottle 30 is sent to the air rinse device 62 withoutbeing sterilized by the second cap sterilizer 63.

Subsequently, the cap 33 sprayed with the chemical agent is conveyed inthe air rinse device 62 and, during that, the inner and outer surfacesof the cap 33 is blown with the sterile hot air. With thisconfiguration, the chemical agent attached to the cap 33 is air-rinsed.Thereafter, the cap 33 is sent from the air rinse device 62 to theplugging device 21.

On the other hand, similarly to the case of the first embodiment, thepreform 31 is sterilized in the preform sterilizer 11, and biaxiallyexpanded and blow-molded in the blow-molding device 13 to be molded tothe bottle 30. The bottle 30 is subjected to the sterilization step inthe container sterilizer 15.

Subsequently, in the filling device 20, a predetermined amount ofculture medium is filled from the mouth part of the bottle 30 into thebottle 30, and the bottle is sent to the plugging device 21. The cap 33sent from the air rinse device 62 is mounted in the mouth part of thebottle 30 in the plugging device 21. In this way, the culture medium isfilled into the bottle 30, and the mouth part is tightly plugged withthe cap 33, whereby a verification bottle 36 is obtained.

Then, the verification bottle 36 filled with the culture medium isconveyed from the product bottle conveyor 22 to the outside. Thereafter,a plurality of verification bottles 36 is conveyed to the constanttemperature storage which is maintained at a predetermined temperatureof 25° C. or more and 40° C. or less, and left and cultured in theconstant temperature storage.

After a lapse of a predetermined period (for example, 3 days or more, orpreferably 7 days or more), all the verification bottles 36 are takenout of the constant temperature storage, and how much microorganismsurvive or propagate in the culture medium in the verification bottle 36is verified. A result obtained by the verification is considered toespecially correspond to the microorganism contamination level betweenthe first cap sterilizer 61 and the second cap sterilizer 63.

Thereafter, the degree of sterilization in the second cap sterilizer 63is adjusted on the basis of the verification result. The adjustment ofthe degree of sterilization may be, for example, appropriately settingthe performance of the second cap sterilizer 63, and specificallyadjusting the spraying amount of the chemical agent in the second capsterilizer 63. Alternatively, an installation area of the second capsterilizer 63 may be adjusted, and the time taken for the bottle to passthrough these devices may be shortened.

In this way, the spraying amount of the chemical agent and the amount ofused hot water are restricted while maintaining the sterilizationperformance required for the second cap sterilizer 63 by appropriatelyadjusting the spraying amount of the chemical agent in the second capsterilizer 63. Therefore, the cost required for sterilization can bereduced, and the environmental load can be reduced. In addition, sincethe installation area of the second cap sterilizer 63 can be reduced,the size of the content filling system 10A can be compact.

In addition, the above embodiments have been described about a system inwhich the preform sterilizer 11 for the preparation sterilization isinstalled in the inlet of the blow-molding device 13, and the blowmolding and the filling of the content are performed while continuouslyconveying, but the invention is not limited thereto. The blow-moldingdevice 13 and the filling device 20 are separately disposed, the bottle30 may be conveyed by an air conveyance or conveyed by a belt conveyortherebetween. In addition, the preform sterilizer 11 for the preparationsterilization is not necessarily provided on a pre-process side of theheater 43, but may be provided in the heater 43, or the conveying wheel18 located on a post-process side of the heater 43, or in theblow-molding device 13. In addition, the preform sterilizer 11 may benot connected to the blow-molding device 13, and may be provided on aconveyor or a chute of the preform 31. Further, the preform sterilizer11 may be replaced with an injection molding machine of the preform 31.In this embodiment, the description has been described about theverification method in the two stages of the preparation sterilizationof the preform sterilizer 11 and the main sterilization of the containersterilizer 15, but the invention is not limited thereto. Thesterilization may be performed through three or more stages.

In addition, the sterilization method of the container is not limited tothe methods described in the embodiments. However, any method may beemployed as long as microorganism are inactivated, and as long asmicroorganism are physically sanitized. Further, in the embodiments, acontamination section from the blow-molding device 13 to the containersterilizer 15 may be set as a space where microorganisms are managedusing a sterilization filter, and an additional sterilization device maybe installed.

1. A verification method of a content filling system which includes apreform sterilizer which sterilizes a preform, a blow-molding devicewhich manufactures a container by blow-molding the preform sterilized bythe preform sterilizer, a container sterilizer which sterilizes thecontainer manufactured by the blow-molding device, a filling devicewhich fills the container sterilized by the container sterilizer with acontent, and a plugging device which plugs the container filled with thecontent by the filling device, the method comprising: a step ofsterilizing the preform by the preform sterilizer; a step ofblow-molding the preform by the blow-molding device to manufacture thecontainer; a step of filling the container with a culture medium by thefilling device without sterilizing the container by the containersterilizer; a step of plugging the container by the plugging device; astep of verifying how much microorganism survive or propagate in theculture medium in the container; and a step of adjusting a degree ofsterilization in the container sterilizer on the basis of a verificationresult.
 2. The verification method of the content filling systemaccording to claim 1, wherein the preform sterilizer sterilizes orsanitizes the preform by chemical spraying, chemical rinsing, steam,sterile water, sterile air, an electronic beam, an X-ray, or anultraviolet ray.
 3. The verification method of the content fillingsystem according to claim 1, wherein the container sterilizer sterilizesor sanitizes the container by chemical spraying, chemical rinsing,steam, sterile water, sterile air, an electronic beam, an X-ray, or anultraviolet ray.
 4. The verification method of the content fillingsystem according to claim 1, wherein the step of adjusting the degree ofsterilization in the container sterilizer includes a step of adjusting aspraying amount of a chemical agent in the container sterilizer.
 5. Theverification method of the content filling system according to claim 1,wherein the step of adjusting the degree of sterilization in thecontainer sterilizer includes a step of setting a sterilizationperformance of the container sterilizer such that a value ΣR₂ becomes(H₀−ΣR₁+ΣI)−FSO or more (herein, H₀ is an initial microorganism level ofthe preform, ΣR₁ is a microorganism reducing level on the preform by thepreform sterilizer, ΣI is an increase in level of microorganism on thepreform or the container between immediately after the preformsterilizer and immediately before the container sterilizer, ΣR₂ is amicroorganism reducing level on the container by the containersterilizer, and FSO is a target value of a microorganism level on thecontainer after the container passes through the container sterilizer).6. A verification method of a content filling system which includes acontainer sterilizer which sterilizes a container, a filling devicewhich fills the container sterilized by the container sterilizer with acontent, a plugging device which plugs the container filled with thecontent by the filling device with a cap, a first cap sterilizer whichsterilizes the cap, an air rinse device which air-rinses the capsterilized by the first cap sterilizer, and a second cap sterilizerwhich sterilizes again the cap air-rinsed by the air rinse device, themethod comprising: a step of sterilizing the container by the containersterilizer; a step of filling the container with a culture medium by thefilling device; a step of sterilizing the cap by the first capsterilizer; a step of air-rinsing the cap by the air rinse device; astep of plugging the container with the cap by the plugging devicewithout sterilizing the cap by the second cap sterilizer; a step ofverifying how much microorganism survive or propagate in the culturemedium in the container; and a step of adjusting a degree ofsterilization in the second cap sterilizer on the basis of averification result.
 7. A content filling system, comprising: a preformsterilizer which sterilizes a preform; a blow-molding device whichmanufactures a container by blow-molding the preform sterilized by thepreform sterilizer; a container sterilizer which sterilizes thecontainer manufactured by the blow-molding device; a filling devicewhich fills the container sterilized by the container sterilizer with acontent; and a plugging device which plugs the container filled with thecontent by the filling device, wherein FSO is −12 or more and −5 or lessto satisfy a relation of H₀−ΣR₁+ΣI−ΣR₂≤FSO (herein, H₀ is an initialmicroorganism level of the preform, ΣR₁ is a microorganism reducinglevel on the preform by the preform sterilizer, ΣI is the increase inlevel of microorganism on the preform or the container betweenimmediately after the preform sterilizer and immediately before thecontainer sterilizer, ΣR₂ is a microorganism reducing level on thecontainer by the container sterilizer, and FSO is a target value of amicroorganism level on the container after the container passes throughthe container sterilizer).